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<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
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    <title>Document</title>
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<body>
    <script>
        let obj = new Object()
        let obj1 = {}
        obj = {
            name: "zhangsan",
            age: 18,
            email: "zhangsan@email.com",
            contact: {
                phone: 188213414,
                telegram: "@zhangsan"
            }
        }
        console.log(obj.contact)
        obj.age = 20
        obj.contact.weChat = "dasd"
        console.log(obj)
    </script>
</body>

</html>